2011

6.7

1985

6.2

1980

8.4

1986

7.4

1989

7.2

1971

7.7

1966

8.0

1998

6.4

2006

6.3

2013

6.9

2002

7.5

1996

7.3

1957

8.1

2012

7.2

2004

7.9

1985

6.6

1994

7.1

1960

7.5

2008

8.1

1957

7.1